This invention relates to solenoid-driven staplers, and particularly to electronic circuits controlling the operation of such staplers.
Conventional staplers include an anvil, a guideway above the anvil through which a driver impels single staples through sheets to be fastened together and into engagement with the anvil, the free ends of the staple being thereby bent to bind the sheets together. In conventional solenoid-operated staplers, the driver, which is coupled to the armature of a solenoid, is actuated by insertion of the material to be stapled into the space between the anvil and the guideway, where the material engages a lever and closes a switch, which in turn actuates the solenoid to drive the staple. Solenoid-driven staplers, in the past, have been subject to overheating with constant, heavy use. Prior art electric staplers have utilized various mechanically operated switches to trigger the stapling operation, prevent chatter, multiple cycles and the like. See, for example, my U.S. Pat. No. 4,491,260 entitled ELECTRIC STAPLER issued to Carlos L. Jimena.